Field of the Invention
The present invention is directed to bi-specific monovalent diabodies that comprise two polypeptide chains and which possess one binding site specific for an epitope of gpA33 and one binding site specific for an epitope of CD3 (i.e., a “gpA33×CD3 bi-specific monovalent diabody”). The present invention also is directed to bi-specific monovalent diabodies that comprise an immunoglobulin Fc Domain (“bi-specific monovalent Fc diabodies”) and are composed of three polypeptide chains and which possess one binding site specific for an epitope of gpA33 and one binding site specific for an epitope of CD3 (i.e., a “gpA33×CD3 bi-specific monovalent Fc diabody”). The bi-specific monovalent diabodies and bi-specific monovalent Fc diabodies of the present invention are capable of simultaneous binding to gpA33 and CD3. The invention is directed to pharmaceutical compositions that contain such bi-specific monovalent diabodies or such bi-specific monovalent Fc diabodies. The invention is additionally directed to methods for the use of such diabodies in the treatment of cancer and other diseases and conditions.
Description of Related Art
I. gpA33
Colorectal cancer is among the most common malignancies of the Western world and is a leading cause of cancer deaths (Silverberg, E. et al. (1989) “Cancer Statistics, 1989,” CA Cancer J Clin. 39(1):3-20). One potentially useful target for colon cancer is the 43 kD transmembrane glycoprotein A33 (gpA33) ((Heath, J. K. et al. (1997) “The Human A33 Antigen Is A Transmembrane Glycoprotein And A Novel Member Of The Immunoglobulin Superfamily,” Proc. Natl. Acad. Sci. (U.S.A.) 94(2):469-474; Ritter, G. et al. (1997) “Characterization Of Posttranslational Modifications Of Human A33 Antigen, A Novel Palmitoylated Surface Glycoprotein Of Human Gastrointestinal Epithelium,” Biochem. Biophys. Res. Commun. 236(3):682-686). gpA33 was first discovered through raising monoclonal murine antibodies against the human pancreatic carcinoma derived cell line ASPC1. One antibody (MAb A33) was found to react with a surface cell protein of 43 kDa, which was therefore designated “gpA33” (Wong, N. A. et al. (2006) “EpCAM and gpA33 Are Markers Of Barrett's Metaplasia,” J. Clin. Pathol. 59(3):260-263).
gpA33 is a transmembrane protein of the junctional adhesion molecule family; Abud, H. E. et al. (2000) “The Murine A33 Antigen Is Expressed At Two Distinct Sites During Development, The ICM Of The Blastocyst And The Intestinal Epithelium,” Mech. Dev. 98(1-2):111-114; Barendswaard, E. C. et al. (1998) “Rapid And Specific Targeting Of Monoclonal Antibody A33 To A Colon Cancer Xenograft In Nude Mice,” Int. J. Oncol. 12(1):45-53; Panjideh, H. et al. (2008) “Biodistribution And Efficacy Of [131I] A33scFv::CDy, A Recombinant Antibody-Enzyme Protein For Colon Cancer,” Int. J. Oncol. 32(4):925-930). Although the functional significance of the A33 antigen is not yet understood, it has been shown to mediate colonic mucosal repair in an animal model of colitis and is homogeneously expressed in >95% of all colorectal carcinomas. A33 expression is uniform across both disease stage and degree of histological differentiation, and the antigen is not detectably secreted or shed into the blood stream (Infante, J. R. et al. (2013) “Safety, Pharmacokinetics And Pharmacodynamics Of The Anti-A33 Fully-Human Monoclonal Antibody, KRN330, In Patients With Advanced Colorectal Cancer,” Eur. J. Cancer. 49(6):1169-1175; Panjideh, H. et al. (2008) “Biodistribution And Efficacy Of [131I] A33scFv::CDy, A Recombinant Antibody-Enzyme Protein For Colon Cancer,” Int. J. Oncol. 32(4):925-930). Conversely, only a few instances of non-gastrointestinal A33 antigen expression have been identified (Johnstone, C. N. et al. (2000) “Characterization Of Mouse A33 Antigen, A Definitive Marker For Basolateral Surfaces Of Intestinal Epithelial Cells,” Am. J. Physiol. Gastrointest. Liver Physiol. 279(3):G500-G510).
In light of the highly restricted expression of the A33 antigen, researchers have explored the possibility of treating A33-associated cancers with antibodies (Infante, J. R. et al. (2013) “Safety, Pharmacokinetics And Pharmacodynamics Of The Anti-A33 Fully-Human Monoclonal Antibody, KRN330, In Patients With Advanced Colorectal Cancer,” Eur. J. Cancer. 49(6):1169-1175; Ackerman, M. E. et al. (2008) “A33 Antigen Displays Persistent Surface Expression,” Cancer Immunol. Immunother. 57(7):1017-1027; Barendswaard, E. C. et al. (2001) “Relative Therapeutic Efficacy Of (125)I-And (131)I-Labeled Monoclonal Antibody A33 In A Human Colon Cancer Xenograft,” J. Nucl. Med. 42(8):1251-1256; Carrasquillo, J. A. et al. (2011) “(124)I-huA33 Antibody PET Of Colorectal Cancer,” J. Nucl. Med. 52(8):1173-1180; Chong, G. et al. (2005) “Phase I Trial Of 131I-HuA33 In Patients With Advanced Colorectal Carcinoma,” Clin. Cancer Res. 11(13):4818-4826; Deckert, P. M. et al. (2000) “Pharmacokinetics And Microdistribution Of Polyethylene Glycol-Modified Humanized A33 Antibody Targeting Colon Cancer Xenografts,” Int. J. Cancer. 87(3):382-390; Johnston, A. P. et al. (2012) “Targeting Cancer Cells: Controlling The Binding And Internalization Of Antibody-Functionalized Capsules” ACS Nano. 6(8):6667-6674; Koppe, M. J. et al. (2005) “Radioimmunotherapy And Colorectal Cancer,” Br. J. Surg. March; 92(3):264-276; Sakamoto, J. et al. (2006) “A Phase I Radioimmunolocalization Trial Of Humanized Monoclonal Antibody HuA33 In Patients With Gastric Carcinoma,” Cancer Sci. 97(11):1248-1254; Scott, A. M. et al. (2005) “A Phase I Trial Of Humanized Monoclonal Antibody A33 In Patients With Colorectal Carcinoma: Biodistribution, Pharmacokinetics, And Quantitative Tumor Uptake,” Clin. Cancer Res. 11(13):4810-4817; Tschmelitsch, J. et al. (1997) “Enhanced Antitumor Activity Of Combination Radioimmunotherapy (131I-Labeled Monoclonal Antibody A33) With Chemotherapy (Fluorouracil),” Cancer Res. 57(11):2181-2186). Likewise fragments of such antibodies have also been evaluated for their potential therapeutic role (Coelho, V. et al. (2007) “Design, Construction, And In Vitro Analysis Of A33scFv::CDy, A Recombinant Fusion Protein For Antibody-Directed Enzyme Prodrug Therapy In Colon Cancer,” Int. J. Oncol. 31(4):951-957).
II. CD3
CD3 is a T cell co-receptor composed of four distinct chains (Wucherpfennig, K. W. et al. (2010) “Structural Biology Of The T-Cell Receptor: Insights Into Receptor Assembly, Ligand Recognition, And Initiation Of Signaling,” Cold Spring Harb. Perspect. Biol. 2(4):a005140; pages 1-14; Chetty, R. et al. (1994) “CD3: Structure, Function And The Role Of Immunostaining In Clinical Practice,” J. Pathol. 173:303-307).
In mammals, the CD3 complex contains a CD3γ chain, a CD3δ chain, and two CD3ϵ chains. These chains associate with a molecule known as the T cell receptor (TCR) in order to generate an activation signal in T lymphocytes. In the absence of CD3, TCRs do not assemble properly and are degraded (Thomas, S. et al. (2010) “Molecular Immunology Lessons From Therapeutic T-Cell Receptor Gene Transfer,” Immunology 129(2):170-177). CD3 is found bound to the membranes of all mature T cells, and in virtually no other cell type (see, Janeway, C. A. et al. (2005) In: IMMUNOBIOLOGY: THE IMMUNE SYSTEM IN HEALTH AND DISEASE,” 6th ed. Garland Science Publishing, NY, pp. 214-216; Sun, Z. J. et al. (2001) “Mechanisms Contributing To T Cell Receptor Signaling And Assembly Revealed By The Solution Structure Of An Ectodomain Fragment Of The CD3ϵ:γ Heterodimer,” Cell 105(7):913-923; Kuhns, M. S. et al. (2006) “Deconstructing The Form And Function Of The TCR/CD3 Complex,” Immunity. 2006 February; 24(2):133-139).
III. Bi-Specific Diabodies
The ability of an intact, unmodified antibody (e.g., an IgG) to bind an epitope of an antigen depends upon the presence of variable domains on the immunoglobulin light and heavy chains (i.e., the VL and VH domains, respectively). The design of a diabody is based on the single chain Fv construct (scFv) (see, e.g., Holliger et al. (1993) “‘Diabodies’: Small Bivalent And Bispecific Antibody Fragments,” Proc. Natl. Acad. Sci. (U.S.A.) 90:6444-6448; US Patent Publication No. 2004/0058400 (Holliger et al.); US 2004/0220388 (Mertens et al.); Alt et al. (1999) FEBS Lett. 454(1-2):90-94; Lu, D. et al. (2005) “A Fully Human Recombinant IgG-Like Bispecific Antibody To Both The Epidermal Growth Factor Receptor And The Insulin-Like Growth Factor Receptor For Enhanced Antitumor Activity,” J. Biol. Chem. 280(20):19665-19672; WO 02/02781 (Mertens et al.); Olafsen, T. et al. (2004) “Covalent Disulfide-Linked Anti-CEA Diabody Allows Site-Specific Conjugation And Radiolabeling For Tumor Targeting Applications,” Protein Eng. Des Sel. 17(1):21-27; Wu, A. et al. (2001) “Multimerization Of A Chimeric Anti-CD20 Single Chain Fv-Fc Fusion Protein Is Mediated Through Variable Domain Exchange,” Protein Engineering 14(2):1025-1033; Asano et al. (2004) “A Diabody For Cancer Immunotherapy And Its Functional Enhancement By Fusion Of Human Fc Region,” Abstract 3P-683, J. Biochem. 76(8):992; Takemura, S. et al. (2000) “Construction Of A Diabody (Small Recombinant Bispecific Antibody) Using A Refolding System,” Protein Eng. 13(8):583-588; Baeuerle, P. A. et al. (2009) “Bispecific T-Cell Engaging Antibodies For Cancer Therapy,” Cancer Res. 69(12):4941-4944).
Interaction of an antibody light chain and an antibody heavy chain and, in particular, interaction of its VL and VH domains forms one of the epitope binding sites of the antibody. In contrast, the scFv construct comprises a VL and VH Domain of an antibody contained in a single polypeptide chain wherein the domains are separated by a flexible linker of sufficient length to allow self-assembly of the two domains into a functional epitope binding site. Where self-assembly of the VL and VH domains is rendered impossible due to a linker of insufficient length (less than about 12 amino acid residues), two of the scFv constructs interact with one another other to form a bivalent molecule in which the VL of one chain associates with the VH of the other (reviewed in Marvin et al. (2005) “Recombinant Approaches To IgG-Like Bispecific Antibodies,” Acta Pharmacol. Sin. 26:649-658).
Natural antibodies are capable of binding to only one epitope species (i.e., mono-specific), although they can bind multiple copies of that species (i.e., exhibiting bi-valency or multi-valency). The art has noted the capability to produce diabodies that differ from such natural antibodies in being capable of binding two or more different epitope species (i.e., exhibiting bi-specificity or multispecificity in addition to bi-valency or multi-valency) (see, e.g., Holliger et al. (1993) “‘Diabodies’: Small Bivalent And Bispecific Antibody Fragments,” Proc. Natl. Acad. Sci. (U.S.A.) 90:6444-6448; US 2004/0058400 (Holliger et al.); US 2004/0220388 (Mertens et al.); Alt et al. (1999) FEBS Lett. 454(1-2):90-94; Lu, D. et al. (2005) “A Fully Human Recombinant IgG-Like Bispecific Antibody To Both The Epidermal Growth Factor Receptor And The Insulin-Like Growth Factor Receptor For Enhanced Antitumor Activity,” J. Biol. Chem. 280(20):19665-19672; WO 02/02781 (Mertens et al.); Mertens, N. et al., “New Recombinant Bi- and Trispecific Antibody Derivatives,” In: NOVEL FRONTIERS IN THE PRODUCTION OF COMPOUNDS FOR BIOMEDICAL USE, A. VanBroekhoven et al. (Eds.), Kluwer Academic Publishers, Dordrecht, The Netherlands (2001), pages 195-208; Wu, A. et al. (2001) “Multimerization Of A Chimeric Anti-CD20 Single Chain Fv-Fc Fusion Protein Is Mediated Through Variable Domain Exchange,” Protein Engineering 14(2):1025-1033; Asano et al. (2004) “A Diabody For Cancer Immunotherapy And Its Functional Enhancement By Fusion Of Human Fc Region,” Abstract 3P-683, J. Biochem. 76(8):992; Takemura, S. et al. (2000) “Construction Of A Diabody (Small Recombinant Bispecific Antibody) Using A Refolding System,” Protein Eng. 13(8):583-588; Baeuerle, P. A. et al. (2009) “Bispecific T-Cell Engaging Antibodies For Cancer Therapy,” Cancer Res. 69(12):4941-4944).
The provision of non-monospecific diabodies provides a significant advantage: the capacity to co-ligate and co-localize cells that express different epitopes. Bivalent diabodies thus have wide-ranging applications including therapy and immunodiagnosis. Bi-valency allows for great flexibility in the design and engineering of the diabody in various applications, providing enhanced avidity to multimeric antigens, the cross-linking of differing antigens, and directed targeting to specific cell types relying on the presence of both target antigens. Due to their increased valency, low dissociation rates and rapid clearance from the circulation (for diabodies of small size, at or below ˜50 kDa), diabody molecules known in the art have also shown particular use in the field of tumor imaging (Fitzgerald et al. (1997) “Improved Tumour Targeting By Disulphide Stabilized Diabodies Expressed In Pichia pastoris,” Protein Eng. 10:1221). Of particular importance is the co-ligating of differing cells, for example, the cross-linking of cytotoxic T cells to tumor cells (Staerz et al. (1985) “Hybrid Antibodies Can Target Sites For Attack By T Cells,” Nature 314:628-631, and Holliger et al. (1996) “Specific Killing Of Lymphoma Cells By Cytotoxic T-Cells Mediated By A Bispecific Diabody,” Protein Eng. 9:299-305).
Diabody epitope binding domains may also be directed to a surface determinant of any immune effector cell such as CD3, CD16, CD32, or CD64, which are expressed on T lymphocytes, natural killer (NK) cells or other mononuclear cells. In many studies, diabody binding to effector cell determinants, e.g., Fcγ receptors (FcγR), was also found to activate the effector cell (Holliger et al. (1996) “Specific Killing Of Lymphoma Cells By Cytotoxic T-Cells Mediated By A Bispecific Diabody,” Protein Eng. 9:299-305; Holliger et al. (1999) “Carcinoembryonic Antigen (CEA)-Specific T-cell Activation In Colon Carcinoma Induced By Anti-CD3×Anti-CEA Bispecific Diabodies And B7×Anti-CEA Bispecific Fusion Proteins,” Cancer Res. 59:2909-2916; WO 2006/113665; WO 2008/157379; WO 2010/080538; WO 2012/018687; WO 2012/162068). Normally, effector cell activation is triggered by the binding of an antigen bound antibody to an effector cell via Fc-FcγR interaction; thus, in this regard, diabody molecules of the invention may exhibit Ig-like functionality independent of whether they comprise an Fc Domain (e.g., as assayed in any effector function assay known in the art or exemplified herein (e.g., ADCC assay)). By cross-linking tumor and effector cells, the diabody not only brings the effector cell within the proximity of the tumor cells but leads to effective tumor killing (see e.g., Cao et al. (2003) “Bispecific Antibody Conjugates In Therapeutics,” Adv. Drug. Deliv. Rev. 55:171-197).
However, the above advantages come at salient cost. The formation of such non-monospecific diabodies requires the successful assembly of two or more distinct and different polypeptides (i.e., such formation requires that the diabodies be formed through the heterodimerization of different polypeptide chain species). This fact is in contrast to mono-specific diabodies, which are formed through the homodimerization of identical polypeptide chains. Because at least two dissimilar polypeptides (i.e., two polypeptide species) must be provided in order to form a non-monospecific diabody, and because homodimerization of such polypeptides leads to inactive molecules (Takemura, S. et al. (2000) “Construction Of A Diabody (Small Recombinant Bispecific Antibody) Using A Refolding System,” Protein Eng. 13(8):583-588), the production of such polypeptides must be accomplished in such a way as to prevent covalent bonding between polypeptides of the same species (Takemura, S. et al. (2000) “Construction Of A Diabody (Small Recombinant Bispecific Antibody) Using A Refolding System,” Protein Eng. 13(8):583-588). The art has therefore taught the non-covalent association of such polypeptides (see, e.g., Olafsen et al. (2004) “Covalent Disulfide-Linked Anti-CEA Diabody Allows Site-Specific Conjugation And Radiolabeling For Tumor Targeting Applications,” Prot. Engr. Des. Sel. 17:21-27; Asano et al. (2004) “A Diabody For Cancer Immunotherapy And Its Functional Enhancement By Fusion Of Human Fc Region,” Abstract 3P-683, J. Biochem. 76(8):992; Takemura, S. et al. (2000) “Construction Of A Diabody (Small Recombinant Bispecific Antibody) Using A Refolding System,” Protein Eng. 13(8):583-588; Lu, D. et al. (2005) “A Fully Human Recombinant IgG-Like Bispecific Antibody To Both The Epidermal Growth Factor Receptor And The Insulin-Like Growth Factor Receptor For Enhanced Antitumor Activity,” J. Biol. Chem. 280(20):19665-19672).
However, the art has recognized that bi-specific monovalent diabodies composed of non-covalently-associated polypeptides are unstable and readily dissociate into non-functional monomers (see, e.g., Lu, D. et al. (2005) “A Fully Human Recombinant IgG-Like Bispecific Antibody To Both The Epidermal Growth Factor Receptor And The Insulin-Like Growth Factor Receptor For Enhanced Antitumor Activity,” J. Biol. Chem. 280(20):19665-19672).
In the face of this challenge, the art has succeeded in developing stable, covalently bonded heterodimeric non-monospecific diabodies (see, e.g., WO 2006/113665; WO/2008/157379; WO 2010/080538; WO 2012/018687; WO/2012/162068; Johnson, S. et al. (2010) “Effector Cell Recruitment With Novel Fv-Based Dual-Affinity Re-Targeting Protein Leads To Potent Tumor Cytolysis And In Vivo B-Cell Depletion,” J. Molec. Biol. 399(3):436-449; Veri, M. C. et al. (2010) “Therapeutic Control Of B Cell Activation Via Recruitment Of Fcgamma Receptor IIb (CD32B) Inhibitory Function With A Novel Bispecific Antibody Scaffold,” Arthritis Rheum. 62(7):1933-1943; Moore, P. A. et al. (2011) “Application Of Dual Affinity Retargeting Molecules To Achieve Optimal Redirected T-Cell Killing Of B-Cell Lymphoma,” Blood 117(17):4542-4551; US Patent Publications No. 2012/0294796 and 2013/0149236). Such approaches involve engineering one or more cysteine residues into each of the employed polypeptide species. For example, the addition of a cysteine residue to the C-terminus of such constructs has been shown to allow disulfide bonding between the polypeptide chains, stabilizing the resulting heterodimer without interfering with the binding characteristics of the bivalent molecule.
Diabodies and other immunoglobulins have been described purporting to have specificity for either or both of gpA33 and CD3 (see, e.g., US Patent Publications No. 2012/0014957; 2012/0034160; 2012/0087858; 2012/0189541; 2012/0195900; 2012/0201746; 2012/0237442; 2012/0263722; 2012/0258108; and 2012/0276608).
Notwithstanding such success, the production of stable, functional heterodimeric, non-monospecific diabodies can be further improved by the careful consideration and placement of the domains employed in the polypeptide chains. The present invention is thus directed to the provision of specific polypeptides that are particularly designed to form, via covalent bonding, heterodimeric diabodies and heterodimeric Fc diabodies that are capable of simultaneously binding gpA33 and CD3.